Homemade Silencer


16 replies to this topic
  • jcheatham

Posted February 06, 2013 - 06:20 PM

#1

Hello I have a 2000 YZ295 and LOVE IT! Before I sent off my head and cylinder I hade the SST pipe and Powercore 2 exhaust set up. Seeing that SST was the worst thing I could possibly have on with my EG295 I had to store it. I switched back over to my full stock set up since my fmf silencer had holes all around it from corrosion. Im going to try and make my own silencer and a carbon fiber tip since I have always wanted to see how carbon fiber is. Im currently going to school for machining so making brackets and such wont be a problem. My question is, does the actual diameter of the silencer make a difference, I know length does. Also the tube in the inside does the size of that matter and do the size of all those holes make a difference. I would like to get this to perform like stock and mabey better. I might have missed some things. any input will help me with my future project!

  • kiwi86

Posted February 06, 2013 - 10:53 PM

#2

I would be quite interested in your results, if you google search Gordon Jennings 2 stroke tuners handbook you will come across a downloadable PDF file on all things to do with two stroke engines. That will have formulas for working out the dimensions for a silencer.
Keep us posted on your progress!

  • BDubb106

Posted February 07, 2013 - 04:00 AM

#3

Im looking forward to your results as well! Should be interesting to see what the average guy can make with some off the shelf materials

  • yamaha7442

Posted February 07, 2013 - 04:43 AM

#4

Everything will make a difference.
Length, diam, packing material, hole size
in the perforated inner core.
...small holes in the perf will be a lot
louder, as well.
Copy what you already have would be a
good place to start
...m4 exhaust makes an adjustable silencer with
different size tips for the outlet, and the
power can be shaped / makes a big difference
just by that little change, and will affect jetting /
heat in the pipe and motor.
...burnt out packing can also lose as much as
2 to 4 hp on a dyno run, depending on engine size, and also make the engine
run like crap, so keep it freshly packed

Edited by yamaha7442, February 07, 2013 - 04:47 AM.


  • souliog

Posted February 07, 2013 - 10:54 AM

#5

I need to take a few pictures, but I was able to cut 4" off the stock silencer and make a shorty out of it. Works good on my 250.

  • prplhzei.t200

Posted February 07, 2013 - 11:02 AM

#6

Whats a YZ295?

  • jcheatham

Posted February 07, 2013 - 12:10 PM

#7

Whats a YZ295?

a YZ295 is a YZ250 bored out to a 295. Eric gorr is one of the best!

  • BDubb106

Posted February 07, 2013 - 01:23 PM

#8

I need to take a few pictures, but I was able to cut 4" off the stock silencer and make a shorty out of it. Works good on my 250.


Not a stock silencer, but I broke my shorty and had this sparky laying around. Needless to say, it is no longer a sparky. Same concept though... I cut it down so it is now 6 inches long.

Posted Image
Posted Image
Posted Image
Posted Image
Posted Image

Edited by BDubb106, February 07, 2013 - 01:24 PM.


Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • jcheatham

Posted February 07, 2013 - 05:50 PM

#9

Not a stock silencer, but I broke my shorty and had this sparky laying around. Needless to say, it is no longer a sparky. Same concept though... I cut it down so it is now 6 inches long.

Posted Image
Posted Image
Posted Image
Posted Image
Posted Image

that looks pretty good mabey I should just buy a cheap silencer on eBay and just cut it down a bit. And then make some carbon fiber tips

  • BDubb106

Posted February 07, 2013 - 05:57 PM

#10

that looks pretty good mabey I should just buy a cheap silencer on eBay and just cut it down a bit. And then make some carbon fiber tips


would probably be cheaper, and get you much closer to a well performing product than experimenting. Just keep in mind. The shorter the silencer the more bottom end, less top end.

I just use this for the more SX oriented tracks where you never get above mid throttle because the runs are so short so I dont need the over rev. Otherwise I use the off the shelf shorty, or standard silencer so you should def experiment with lengths. I usually find banged up silencers on ebay and cut/ weld them just to experiment. I have not paid over $10 for a silencer and I have a full shelf of them of all diff lengths. Most of which I have never used, but plan on playing with this summer.

  • Chill_MotoX

Posted February 08, 2013 - 08:07 AM

#11

It would be cool and maybe easier if you can make a can and just have it so that can utilize the enduro engeneering spark arrestor end cap... Also seen lexx carbon fiber tips but not sure if it's for the 2 stroke...

  • kiwi86

Posted February 11, 2013 - 09:57 PM

#12

Any more progress?

  • poldies4

Posted February 12, 2013 - 03:48 AM

#13

would probably be cheaper, and get you much closer to a well performing product than experimenting. Just keep in mind. The shorter the silencer the more bottom end, less top end.

I just use this for the more SX oriented tracks where you never get above mid throttle because the runs are so short so I dont need the over rev. Otherwise I use the off the shelf shorty, or standard silencer so you should def experiment with lengths. I usually find banged up silencers on ebay and cut/ weld them just to experiment. I have not paid over $10 for a silencer and I have a full shelf of them of all diff lengths. Most of which I have never used, but plan on playing with this summer.


Great idea! I might do this myself...

  • jcheatham

Posted February 12, 2013 - 04:38 AM

#14

Any more progress?

not much unfortunitly. I've been looking around and thinking its not about length, but volume. I dont know if its true or not but it makes since. More volume the more top end and the quieter it will be.

  • jcheatham

Posted February 12, 2013 - 04:38 AM

#15

Any more progress?

not much unfortunitly. I've been looking around and thinking its not about length, but volume. I dont know if its true or not but it makes since. More volume the more top end and the quieter it will be.

  • kiwi86

Posted February 12, 2013 - 10:07 AM

#16

I read on another thread that a short silencer will increase bottom end. That kind of flies in the face of what I thought was the case with intake/exhaust tracts, that you make them long and skinny for bottom end, and short and fat for top end.

http://www.thumperta...ns#entry8365640

Edited by kiwi86, February 12, 2013 - 10:21 AM.


  • BDubb106

Posted February 12, 2013 - 11:07 AM

#17

I read on another thread that a short silencer will increase bottom end. That kind of flies in the face of what I thought was the case with intake/exhaust tracts, that you make them long and skinny for bottom end, and short and fat for top end.

http://www.thumperta...ns#entry8365640


yea, you have it backwards.





Related Content

Forums
Photo

Kx 250f vs yz 250 vs yz125 by kxrider1001


Dirt Bike   General Dirt Bike Forums   What bike should I buy?
  • 9 replies
Forums
Photo

Worth rebuilding a '00 YZ250? by mr.boombastic


Dirt Bike   Make / Model Specific   Yamaha   Yamaha 2-Stroke
  • 10 replies
Reviews

Yamaha YZ85 2013 by Chris.GVS


Yamaha YZ85 2013
  • - - - - -
  • 0 reviews
Forums
Photo

2015 YZ125 "intro" by Racer X by YamaLink


Dirt Bike   Make / Model Specific   Yamaha   Yamaha 2-Stroke
  • 18 replies
Forums
Photo

yz85 vs cr125 power. by vertox


Dirt Bike   General Dirt Bike Forums   What bike should I buy?
  • 21 replies
 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.